The Federal Reserve cut interest rates for the first time in more than a decade in July, citing trade uncertainties and muted inflation. The central bank is widely expected to cut another quarter point when the Federal Open Market Committee holds its two-day meeting starting Sept. 17.

"In the U.S., our economists have revised down their growth forecasts, largely as a result of trade uncertainty," Folkerts-Landau said. "Manufacturing is contracting and there are cracks in the otherwise strong labor market."